Author: obrien
Date: Fri Oct 26 15:44:29 2012
New Revision: 242137
URL: http://svn.freebsd.org/changeset/base/242137
Log:
Iterate rather than use recursion. We can blow out the kernel stack if there
is a long chain of fork(2)s.
Added:
head/tools/regression/filemon/timed-forkb.c (contents, props changed)
Modified:
head/sys/dev/filemon/filemon_wrapper.c
head/tools/regression/filemon/Makefile
Modified: head/sys/dev/filemon/filemon_wrapper.c
==============================================================================
--- head/sys/dev/filemon/filemon_wrapper.c Fri Oct 26 15:21:23 2012
(r242136)
+++ head/sys/dev/filemon/filemon_wrapper.c Fri Oct 26 15:44:29 2012
(r242137)
@@ -82,15 +82,14 @@ filemon_pid_check(struct proc *p)
{
struct filemon *filemon;
- TAILQ_FOREACH(filemon, &filemons_inuse, link) {
- if (p->p_pid == filemon->pid)
- return (filemon);
+ while (p->p_pptr) {
+ TAILQ_FOREACH(filemon, &filemons_inuse, link) {
+ if (p->p_pid == filemon->pid)
+ return (filemon);
+ }
+ p = p->p_pptr;
}
-
- if (p->p_pptr == NULL)
- return (NULL);
-
- return (filemon_pid_check(p->p_pptr));
+ return (NULL);
}
static void
Modified: head/tools/regression/filemon/Makefile
==============================================================================
--- head/tools/regression/filemon/Makefile Fri Oct 26 15:21:23 2012
(r242136)
+++ head/tools/regression/filemon/Makefile Fri Oct 26 15:44:29 2012
(r242137)
@@ -1,15 +1,33 @@
# $FreeBSD$
-PROG= filemontest
+BINS= \
+ filemontest \
+ timed-forkb
+
+bins: filemontest timed-forkb
+all: bins
NO_MAN=
WARNS?= 6
CFLAGS+= -I${.CURDIR}/../../../sys
+# Should be "WITHOUT_CTF=" below, but stupid infastrurture fails:
+# "/usr/share/mk/bsd.own.mk", line 489: WITH_CTF and WITHOUT_CTF can't both be
set.
+WITHOUT_CDDL=
+
+CLEANFILES+= ${BINS}
+
+tests: bins
+ kldstat | grep filemon
+ ${MAKE} test
+ ./timed-forkb
+ @echo "filemon(4) tests passed."
+
# Cannot use .OBJDIR -- 'filemontest' expects 'test_script.sh' in .
-test: ${PROG} clean-test
-.for BIN in ${PROG} ${PROG}32
+#FILEMONTEST32= filemontest32
+test: filemontest clean-test
+.for BIN in filemontest ${FILEMONTEST32}
cd ${.CURDIR} ; \
for A in 1 2 3 4 5 6 7 8 9 0; do \
for B in 1 2 3 4 5 6 7 8 9 0; do \
Added: head/tools/regression/filemon/timed-forkb.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/tools/regression/filemon/timed-forkb.c Fri Oct 26 15:44:29 2012
(r242137)
@@ -0,0 +1,177 @@
+/*-
+ * Copyright (c) 2012 David O'Brien
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/types.h>
+#include <sys/resource.h>
+#include <sys/sysctl.h>
+#include <sys/wait.h>
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <err.h>
+#include <assert.h>
+
+#ifndef SLEEP
+#define SLEEP 20 /* seconds */
+#endif
+
+int verbose;
+
+static void
+usage(void)
+{
+ fprintf(stderr, "usage: %s\n", getprogname());
+ fprintf(stderr, "\t\t-n : length of fork(2) chain\n");
+ fprintf(stderr, "\t\t-t : limit run-time seconds\n");
+ exit(1);
+ /* NOTREACHED */
+}
+
+void term(int);
+void
+term(int signum)
+{
+
+ if (getpid() == getpgrp() || verbose) {
+ fprintf(stderr,
+ "pid %d pgroup %d (ppid %d): Received SIGTERM(%d), exiting...\n",
+ getpid(), getpgrp(), getppid(), signum);
+ }
+ exit(1);
+}
+
+void angel_of_mercy(int);
+void
+angel_of_mercy(int sig __unused)
+{
+
+ signal(SIGALRM, SIG_IGN); /* ignore this signal */
+ printf("Master process: alarmed waking up\n");
+ killpg(0, SIGTERM);
+ return;
+}
+
+int bombing_run(unsigned, int);
+int
+bombing_run(unsigned chainlen, int stime)
+{
+ struct rusage ru;
+ pid_t pid, cpid;
+ int status;
+
+ if (chainlen) {
+ switch (pid = fork()) {
+ case -1:
+ errx(1, "%s: can't fork", __func__);
+
+ case 0:
+ /* This is the code the child runs. */
+ bombing_run(--chainlen, stime);
+ break;
+
+ default:
+ /* This is the code the parent runs. */
+ if (getpid() == getpgrp()) {
+ signal(SIGALRM, angel_of_mercy);
+ alarm(stime); // time for bombing run...
+ cpid = wait4(pid, &status, 0, &ru);
+ alarm(0);
+ printf(
+ "Cleanly shutting down - pid %d pgroup %d (ppid %d)\n",
+ getpid(), getpgrp(), getppid());
+ } else {
+ cpid = wait4(pid, &status, 0, &ru);
+ }
+ }
+ }
+
+ return 0;
+}
+
+int
+main(int argc, char *argv[])
+{
+ time_t start /*,tvec*/;
+ char *endptr, *ctm;
+ size_t len;
+ int nflag, tflag;
+ int ch, k, maxprocperuid;
+
+ (void)signal(SIGTERM, term);
+
+ nflag = 0;
+ tflag = SLEEP;
+
+ start = time(NULL);
+ ctm = ctime(&start);
+ ctm[24] = '\0'; // see: man 3 ctime
+ fprintf(stderr, "*** fork() generation started on \"%s\" ***\n", ctm);
+
+ while ((ch = getopt(argc, argv, "n:t:v")) != -1)
+ switch (ch) {
+ case 'n':
+ nflag = strtol(optarg, &endptr, 10);
+ if (nflag <= 0 || *endptr != '\0')
+ errx(1, "illegal number, -n argument -- %s",
+ optarg);
+ break;
+ case 't':
+ tflag = strtol(optarg, &endptr, 10);
+ if (tflag <= 0 || *endptr != '\0')
+ errx(1, "illegal number, -t argument -- %s",
+ optarg);
+ break;
+ case 'v':
+ ++verbose;
+ break;
+ default:
+ usage();
+ }
+ argv += optind;
+
+ if (!nflag) {
+ len = sizeof(maxprocperuid);
+ k = sysctlbyname("kern.maxprocperuid", &maxprocperuid, &len,
+ NULL, 0);
+ assert(k != ENOMEM);
+ /* Try to allow a shell to still be started. */
+ nflag = maxprocperuid - 10;
+ }
+
+ // Ensure a unique process group to make killing all children easier.
+ setpgrp(0,0);
+ printf(" pid %d pgroup %d (ppid %d), %d fork chain over %d sec\n",
+ getpid(), getpgrp(), getppid(), nflag - 1, tflag);
+
+ return bombing_run(nflag, tflag);
+}
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
